Solar Terrestrial Activity Report [Image] Last update January 18, 2002 at 04:10 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update January 1, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 1, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 1, 2002)] [Historical solar and geomagnetic data charts 1954-2001 (last update January 12, 2002)] Recent development The geomagnetic field was quiet to slightly unsettled on January 17. Solar wind speed ranged between 350 and 422 km/sec. Solar flare activity was low. Solar flux was 211.8, the planetary A index was 6 (3-hour K indices: 3112 2312, Boulder K indices: 3112 2321). Region 9778 decayed further and could become spotless today. Region 9779 was quiet and stable, as was region 9781. Region 9782 was mostly unchanged and remains capable of producing occasional minor M class flares. Region 9783 was mostly quiet and stable. Region 9785 developed slowly and could produce minor M class flares. Region 9786 developed early in the day but appeared to be decaying towards the end of the day. New region 9787 rotated partly into view at the southeast limb. Flares and CMEs A total of 7 C class events were recorded on January 17. Region 9775 produced a C2.9 flare at 02:16 and a C4.2 flare at 03:12 UTC. Region 9783 generated a C2.4 flare at 12:15 UTC. The background x-ray flux is at the class C1 level. Coronal holes A small coronal hole in the southern hemisphere was in a geoeffective position on January 16. Forecast The geomagnetic field is expected to be quiet to unsettled on January 18-19. A coronal stream could begin to influence the field on January 19 and cause a few unsettled to active intervals. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor to fair. Coronal holes (1) Coronal mass M and X class flares (3) ejections (2) [Coronal hole indicator][CME indicator] [M and X class flare indicator] 1) Effects from a coronal hole could reach earth within the next 5 days. 2) Material from a CME is likely to impact earth within 96 hours. 3) There is a possibility of either M or X class flares within the next 48 hours. Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability. Active solar regions (Recent map) Solar Date Actual no. Location at region numbered sunspots midnight Area Classification Comment 9776 2002.01.07 N08W76 plage 9777 2002.01.08 S06W53 plage 9778 2002.01.08 3 S14W50 0020 CSO 9779 2002.01.08 3 N29W53 0120 CSO 9781 2002.01.11 1 S04W14 0100 HSX 9782 2002.01.11 10 N06W08 0270 DKO 9783 2002.01.12 5 S12E12 0210 CAO 9784 2002.01.13 S28E05 plage 9785 2002.01.13 12 N10E01 0250 DAO 9786 2002.01.16 7 S26W06 0050 DSO 9787 2002.01.17 1 S08E85 0120 HHX Total number of sunspots: 42 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.8 2000.11 178.8 106.8 112.7 (-1.8) 2000.12 173.6 104.4 112.0 (-0.7) 2001.01 166.6 95.6 108.7 (-3.3) 2001.02 146.6 80.6 104.1 (-4.6) 2001.03 177.7 113.5 104.8 (+0.7) 2001.04 177.7 107.7 107.6 (+2.8) 2001.05 147.1 96.6 108.7 (+1.1) 2001.06 173.0 134.0 109.8 (+1.1) 2001.07 131.3 82.2 (111.2 predicted, +1.4) 2001.08 162.9 106.8 (111.7 predicted, +0.5) 2001.09 233.2 150.7 (110.7 predicted, -1.0) 2001.10 207.6 125.6 (108.0 predicted, -2.7) 2001.11 210.6 106.5 (106.3 predicted, -1.7) 2001.12 235.1 131.8 (103.0 predicted, -3.3) 2002.01 219.4 (1) 98.4 (2) (99.4 predicted, -3.6) 1) Running average based on the daily 20:00 UT solar flux value at 2800 MHz. 2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number is typically 25-40% less. This report has been prepared by Jan Alvestad. It is based partly on my own observations and interpretations, and partly on data from sources noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News]